Medium Radius

Medium Radius: Navigating the Well Path in Hold

In the world of directional drilling, the term "medium radius" refers to a specific type of well trajectory characterized by a moderate rate of deviation. This rate is typically defined as between 8 and 12 degrees of change in wellbore direction for every 100 feet of drilled depth.

Why is Medium Radius Important?

Medium radius wells offer a balance between controlled deviation and efficient drilling. They are commonly employed when:

• Targeting a specific subsurface horizon: By maintaining a moderate deviation rate, medium radius wells can effectively reach targeted formations while minimizing the risk of excessive dog-legging or exceeding the allowable wellbore inclination.
• Optimizing wellbore stability: The controlled deviation prevents sudden changes in wellbore pressure and stress, promoting stability and minimizing the risk of wellbore collapse or other issues.
• Maintaining drilling efficiency: Compared to high-radius wells, medium radius wells require less complex drilling equipment and can be drilled more efficiently, leading to faster drilling times and reduced costs.

Well Deviation Change at 8° per 100 ft:

A well deviation change of 8 degrees per 100 feet falls within the typical range for medium radius wells. This means that for every 100 feet drilled vertically, the wellbore will change direction by 8 degrees.

Visualizing the Deviation:

Imagine a straight line representing the vertical wellbore. As drilling progresses, the wellbore begins to deviate from this straight path. With an 8° per 100 ft deviation, the wellbore will gradually curve away from the vertical line, forming a smooth arc with a specific radius.

Applications of Medium Radius Wells:

Medium radius wells are commonly used in various drilling scenarios, including:

• Onshore and offshore oil and gas exploration and production: Medium radius wells are particularly useful for reaching targets at moderate depths and inclinations.
• Geothermal energy development: These wells are employed to access underground geothermal resources, providing a sustainable source of energy.
• Water resource management: Medium radius wells are used for extracting groundwater resources, ensuring efficient and sustainable water supply.

Conclusion:

Medium radius wells, with their characteristic deviation rates, provide a valuable tool for navigating complex subsurface environments. By balancing controlled deviation and drilling efficiency, they offer a practical and effective solution for reaching targeted formations while maintaining wellbore stability. The understanding of medium radius concepts and their application is crucial for optimizing well planning and execution in various drilling scenarios.